If 25/(x/5) = (1/25)/125 then x = ?

Question

(A) 5^(-2)
(B) 5^2
(C) 5^3
(D) 5^8
(E) 5^11

khaynes3 · Answer

rewrite as:
25*(5/x) = (1/25)*(1/125)
(5^3)/x = (1/(5^2))*(1/(5^3))
1/x = (1/(5^2))*(1/(5^3))*(1/(5^3))
1/x = 1/(5^7)
x = (5^7)

Where did you get that answer?

subhashghosh · Answer

=> 125/x = 1/25 * 1/125

=> x = 5^3 * 5^2 * 5^3 => x = 5^8

Perhaps the answer is D.

I think the answer choices should read 5^-2, 5^2, 5^3, 5^8, 5^11.

@banksy, could you please confirm the answer choices ?

khaynes3 · Answer

Oops, I agree with the (5^8), bad adding skills.

scbguy · Answer

Why isnt it

25/(x/5)=(1/25)/125
25*5/x=1/25*1/125
125/x=1/(125)(25)
1/x=1/25
x=25
x=5^2

fluke · Answer

\frac{125}{x} = \frac{1}{125*25}

If we cross multiply;

x = 125*125*25

x = 5^3*5^3*5^2

x = 5^{(3+3+2)} = 5^8

scbguy · Answer

got it thanks

, i thought we could cancel out 125

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